Sudden cardiac arrest (colloquially “a heart attack”) is a serious condition that frequently results in death. The speed with which life saving personnel can respond to a sudden cardiac arrest is one of the most important, if not the most important, determinant of a successful outcome for a victim of sudden cardiac arrest. For example, it is said that likelihood of surviving a sudden cardiac arrest falls ten percent for every minute in which assistance (e.g., defibrillation or chest compressions) is delayed. As a result, speed of response can be very important to a heart attack victim.
One typical mode of treatment for sudden cardiac arrest is to “shock” the heart back into a steady beating pattern using an external defibrillator. Such a defibrillator commonly includes a pair of electrodes that are placed on the victim's chest and are connected electrically to a power unit. In hospitals, such a defibrillator is typically used by a “code team” that responds to “codes” issued by attending caregivers. Such teams use advanced defibrillators that they can control for a number of parameters, such as by displaying a patient's ECG and blood oxygen level, and by letting caregivers set the power level to be delivered to the victim and provide pacing inputs.
Such professional defibrillators, known as Advanced Life Support, or ALS, defibrillators can be intimidating for other staff, including medically-trained staff such as shift nurses. As a result, a patient may have to wait for a code team to arrive even though an otherwise-competent caregiver is nearby.